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Weitek P9000 Video Graphics Processor

Weitek produced multimedia chips in the P9000 line for popular video cards released by Diamond and Orchid in 1994. After Weitek went out of business in 1997, it was absorbed into the Brooktree Division of Rockwell Semiconductor, which survives as an independent spin-off, Conexant Systems.

Although the Weitek P9000 did not support three-dimensional graphics, it was popular with advanced computer users, supporting OS/2 and Linux platforms in addition to Windows-based applications. As a frame buffer and the driving force in graphics adapter cards that were the cutting edge for their day, P9000 chipsets were teamed with up to 2 Mbytes of 32-bit video random-access memory (VRAM) and usually a Weitek 5x86 VGA chip, such as the 5186. Providing on-board video RAM freed other computer resources, resulting in fewer bottlenecks and more efficient operations. Weitek followed the successful P9000 with the P9001, nicknamed the "Viper", a peripheral component interconnect (PCI) version of the P9000. An even later version, the P9100, was essentially a P9000 with a built-in Weitek 5286 chip that was also known as the Viper Pro/SE.

The Diamond Viper VLB graphics-adapter card employs the Weitek P9000 super video graphics adapter (SVGA) chipset with 1 or 2 Mbytes of video RAM, 256 kilobytes of dynamic RAM (DRAM), and the Oak OTI-087 chipset with a VESA local bus interface. The random-access memory/digital-to-analog converter or RAMDAC was a Brooktree Bt485 clocked at 135 MHz, but often only verified to 110 MHz. As one of the first SVGA VLB graphics adapter cards available, the Oak OTI-087 provided 256 colors at 1024 x 768 pixels for non-interlaced monitors and 1280 x 1024 for interlaced video. While the maximum dot-clock was 80 MHz, the P9000 chipsets were usually coupled with the OTI068 clock generator for a maximum frequency of 78 MHz.